Tolerance, Dependence, Addiction: What's the Difference?

This blog post is archived and is no longer being updated. For the latest content, please visit the main Drugs & Health Blog page.
Image
A word cloud of addiction and related words

Many people think drug addiction, dependence, and tolerance are pretty much the same thing. But in fact, each term means something very different about how drugs affect a person’s body and brain. Learning the difference is important.

Tolerance

Tolerance happens when a person no longer responds to a drug in the way they did at first. So it takes a higher dose of the drug to achieve the same effect as when the person first used it. This is why people with substance use disorders use more and more of a drug to get the “high” they seek.

Dependence

Dependence means that when a person stops using a drug, their body goes through “withdrawal”: a group of physical and mental symptoms that can range from mild (if the drug is caffeine) to life-threatening (such as alcohol or opioids, including heroin and prescription pain relievers). Many people who take a prescription medicine every day over a long period of time can become dependent; when they go off the drug, they need to do it gradually, to avoid withdrawal discomfort. But people who are dependent on a drug or medicine aren’t necessarily addicted.

Addiction

Unlike tolerance and dependence, addiction is a disease; but like tolerance and dependence, addiction can result from taking drugs or alcohol repeatedly. If a person keeps using a drug and can’t stop, despite negative consequences from using the drug, they have an addiction (also called a severe substance use disorder). But again, a person can be dependent on a drug, or have a high tolerance to it, without being addicted to it.

Learn more: Marijuana withdrawal is real.

Find Help Near You

Use the SAMHSA Treatment Locator to find substance use or other mental health services in your area. If you are in an emergency situation, this toll-free, 24-hour hotline can help you get through this difficult time: call 1-800-273-TALK, or visit the Suicide Prevention Lifeline. We also have step by step guides on what to do to help yourself, a friend or a family member.

Related Articles

Say What? “Relapse”
July 2018

A person who's trying to stop using drugs can sometimes start using them again. Fortunately, treatment can help to lower...